Abstract

We propose a fast quality metric for depth maps, called FDQM, which efficiently measures the impacts of depth map errors on the qualities of synthesized views in multi-view video plus depth applications. Assuming that neighboring pixels have similar disparities, we estimate view synthesis distortions in the depth map domain without performing the actual view synthesis. Specifically, we compute the distortions at pixel positions, which are specified by reference disparities and distorted disparities, respectively. We then integrate those pixel-wise distortions into an FDQM score by employing a spatial pooling scheme, which considers occlusion effects and the characteristics of human visual attention. As a benchmark of depth map quality assessment, we perform a subjective evaluation test for intermediate views, which are synthesized from compressed depth maps at various bit-rates. We compare the subjective results with objective metric scores. Experimental results demonstrate that the proposed FDQM yields highly correlated scores to the subjective ones. Moreover, FDQM requires at least 10 times less computations than conventional quality metrics, since it does not perform the actual view synthesis.